Angina Risk Stratification and Its Clinical Implications

Understanding Angina Classification by the Canadian Cardiovascular Society

The Canadian Cardiovascular Society (CCS) has established a four-tier classification system for angina, which helps physicians assess the severity of angina symptoms and guide appropriate treatment strategies. This classification is based on the level of physical activity that triggers angina symptoms.

CCS Class I: Minimal Limitation

In Class I angina, most patients do not experience chest pain during normal daily activities. Symptoms typically occur only after intense, strenuous exertion such as climbing hills or running approximately 1,000 meters. This classification indicates that the heart is only mildly affected and that the risk of complications is relatively low.

CCS Class II: Mild Limitation

Class II angina occurs during moderate physical activities that are part of everyday life. Examples include grocery shopping, walking 500 meters, carrying a kettle, or climbing stairs. These symptoms suggest a noticeable but not severe limitation in physical capacity and may indicate the need for lifestyle adjustments or mild medical intervention.

CCS Class III: Marked Limitation

Patients with Class III angina experience chest discomfort even with minimal physical exertion. Activities such as walking 20 meters or getting up to pour a glass of water can trigger symptoms. This level of angina indicates a significant impairment in daily functioning and signals a higher risk of cardiovascular events, necessitating more aggressive medical management.

CCS Class IV: Severe Angina at Rest

Class IV angina, also known as resting angina, occurs even when the patient is inactive, such as sitting and conversing. This is the most severe form of angina and is considered a medical emergency. It often indicates critical blockages in the coronary arteries and a high risk of myocardial infarction or heart attack.

Recognizing High-Risk Angina Symptoms

Duration and associated symptoms are key indicators of angina severity. If chest pain lasts more than 20 minutes, it is considered a red flag for potential cardiac complications. Additionally, if angina is accompanied by symptoms such as intense dizziness, temporary vision loss (blackouts), or excessive cold sweating, it should be treated as a high-risk warning. These signs may suggest unstable angina or an impending heart attack, requiring immediate medical attention.